Drew
I won't argue fan design with you
I ask you to stop and think about this for a moment
I have yet to see an RV furnace use anything other than the STD Cheepie squirrel cage, in the RV heater box for the moving the heated air through the ducts
Given that all use the same basic design
And the ducts are not restricted
What i said holds true
We are not talking about theoretical design efficiency here
You want to use less battery energy with the RV furnace you WILL move less air
If you test the heaters you mentioned
The one with the smaller motor, 5.5 amp drain will move less CuFt of warm air through the RV
